The Grand Shogun was one of the old Samurai Rangers predating the current team. not much is known about him. 300 years ago,when the BullZord had rampaged along the countryside, he had entrusted the Guardians, friends of the Samurai to guard the BullZord with their very lives. He ordered that it remain sealed for all eternity. Little did he know that in the future, a young boy named Cody would have the ability to communicate with it.
When the BullZord was finally freed and utilized by Jayden Shiba roughly 3 centuries later, the Grand Shogun's apparition appeared before Jayden, and promised him that now that the BullZord was free, their power now belongs to him (and the new Rangers). Thus the Grand Shogun and his Shogun Ranger compatriots' powers are transferred onto the new Samurai Rangers via the Shogun Disk.